Sometimes you’ve just got to wait for your gigantic telecom merger to take place.

Per Macworld, AT&T has pushed back the expected date of its proposed US$39 billion merger with T-Mobile USA, saying now that the deal will close in the first half of 2012.

When it announced the deal in April, AT&T said it expected to get regulatory approval within 12 months. But a lawsuit by the U.S. Department of Justice and seven states, filed on Aug. 31, made that forecast unrealistic. The suit isn’t even scheduled to go to trial until Feb. 13, 2012.

AT&T laid out the new timeline in a document filed with the U.S. Securities and Exchange Commission on Thursday.

The DOJ has argued that the merger would raise prices and stifle innovation by eliminating a low-price competitor. AT&T’s plans have also come under attack from some consumer groups and from Sprint Nextel and C-Spire Wireless, a smaller mobile operator. Earlier this week, a federal judge allowed a lawsuit by Sprint and C-Spire to go forward. Those carriers argue that the merger would make it harder for them to acquire new types of handsets because of exclusive deals that a combined AT&T and T-Mobile could make.